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Featured researches published by Yoshiharu Sakata.


Acta Oto-laryngologica | 1989

Analysis of Body Sway Pattern after Alcohol Ingestion in Human Subjects

Takeshi Kubo; Yoshiharu Sakata; Toru Matsunaga; A. Koshimune; Shun-ichi Sakai; K. Ameno; I. Ijiri

Movements of the centre of gravity during 60 s of standing with eyes closed and eyes open were analysed before and after alcohol ingestion up to 8 h in 37 healthy human subjects. Blood alcohol and acetaldehyde concentrations (BAC and BAcHC) were measured simultaneously. Among the parameters analysed, area of posturogram was the most sensitive indicator; it increased to 3.8 times that of the control value at 60 min, after 3.5 ml/kg of ingested whisky (mean BAC of this group was 1.4 mg/ml), with the eyes open. The Romberg ratio, which denotes eyes closed relative to eyes open, remained constant. By contrast, there was little change in stabilometry in cases of 1.2 ml/kg of whisky ingestion (mean BAC at 60 min was 0.58 mg/ml). It is considered that body sway starts to increase when the BAC level exceeds 0.6 mg/ml on average; this value is only higher than the threshold of positional alcohol nystagmus. Correlation coefficients between BAC and each parameter of the stabilogram in the eyes open condition, such as area, X- and Y-axis diameters, and velocity of body sway, were 0.53, 0.45 and 0.48, respectively (p less than 0.01). There was no positive correlation between BAcHC and these parameters.


Cancer | 1988

A study of the late effects of radiotherapy and operation on patients with maxillary cancer: A survey more than 10 years after initial treatment

Shun-ichi Sakai; Takeshi Kubo; Nozomu Mori; Mahito Itoh; Mamoru Miyaguchi; Shigeo Kitaoku; Yoshiharu Sakata; Hajime Fuchihata

One hundred seventy‐one maxillary carcinoma patients who survived more than 10 years after initial treatment were surveyed. Performance status was unrestricted in 35.1% of the patients, slightly restricted in 34.5%, moderately restricted in 21.1%, restricted in 7.0%, and very restricted in 2.3%. Radiation‐induced cataracts on the affected side occurred in 100% of the patients treated with radiation. Good visual acuity was maintained in only 65.8% of the patients, even on the contralateral side. Fifty‐five percent of the patients retained symmetric facial animation due to our policy of conservative therapy. Restricted mouth opening occurred in 32.2% of the patients, taking liquid diet in 21.1%, and middle ear effusion in 26.3%, which were closely linked to maxillectomy operation. This study suggests that avoiding excess radiation dosage, strict control of radiation field, adaption of two portals with 60 grades wedge pair filter, use of appropriate protectors, limiting removal at the maxillactomy, and postoperative care for trismus or tympanic effusion are necessary.


Otology & Neurotology | 2011

Prognostic factors of peripheral facial palsy: multivariate analysis followed by receiver operating characteristic and Kaplan-Meier analyses.

Norihiko Takemoto; Arata Horii; Yoshiharu Sakata; Hidenori Inohara

Objective: To search for prognostic predictors and reexamine the usefulness of electroneurography (ENoG) in predicting the prognosis of peripheral facial palsy using statistical methods. Study Design: Prospective study. Setting: Tertiary referral center. Patients: Consecutive 142 patients with Bells palsy and 26 with Ramsay Hunt syndrome treated with steroid plus antiviral agents. Interventions: Multivariate analysis was used to identify which factors, including Yanagihara grading score and ENoG, predict better recovery. Receiver operating characteristic (ROC) curves were constructed for ENoG and grading score. The cumulative recovery rate by ENoG was calculated using Kaplan-Meier analysis. Recovery was defined as the improvement of grading score to 36 points or more (full score, 40) without synkinesis. Results: Multivariate analysis revealed that Ramsay Hunt syndrome, the worst grading score and ENoG were the significant prognostic predictors. The area under the ROC curve for ENoG was broader than those for grading score, indicating that ENoG was superior to grading score in terms of accuracy for prognosis prediction. The ROC curve revealed that more than 85% degeneration on ENoG had the best specificity (77.8%) and sensitivity (71.4%) to predict nonrecovery. When ENoG was subjected to the analysis of cumulative recovery rate using Kaplan-Meier plots, patients with more than 85% degeneration on ENoG had significantly poorer prognosis. Conclusion: ENoG was the most effective factor for prediction of the prognosis of peripheral facial palsy, and more than 85% degeneration had the best specificity and sensitivity to predict nonrecovery.


Acta Oto-laryngologica | 2000

Effects of Amygdala or Hippocampus Lesion on Hypergravity-induced Motion Sickness in Rats

Atsuhiko Uno; Noriaki Takeda; Arata Horii; Yoshiharu Sakata; Atsushi Yamatodani; Takeshi Kubo

We examined the effects of amygdala lesion (AL) or hippocampal lesion (HL) on hypergravity-induced motion sickness in rats. Rats do not vomit, but the behavior known as pica, the eating of non-nutritive substances such as kaolin, can be used as an index of motion sickness. In the present study, hypergravity-induced kaolin intake and apomorphine-induced kaolin intake were measured before and after brain lesions. After AL, hypergravity-induced kaolin intake and the ratio of the hypergravity- to apomorphine-induced kaolin intakes were decreased. These results indicate that AL suppressed motion sickness more than pica behavior itself, suggesting that the amygdala plays an important role in the development of motion sickness in rats. Conversely, after HL, hypergravity-induced kaolin intake was increased, as was the ratio of the hypergravity- to apomorphine-induced kaolin intakes. These results indicate that HL aggravates motion sickness induced by hypergravity in rats, suggesting that the hippocampus counteracts motion sickness.We examined the effects of amygdala lesion (AL) or hippocampal lesion (HL) on hypergravity-induced motion sickness in rats. Rats do not vomit, but the behavior known as pica, the eating of non-nutritive substances such as kaolin, can be used as an index of motion sickness. In the present study, hypergravity-induced kaolin intake and apomorphine-induced kaolin intake were measured before and after brain lesions. After AL, hypergravity-induced kaolin intake and the ratio of the hypergravity- to apomorphine-induced kaolin intakes were decreased. These results indicate that AL suppressed motion sickness more than pica behavior itself, suggesting that the amygdala plays an important role in the development of motion sickness in rats. Conversely, after HL, hypergravity-induced kaolin intake was increased, as was the ratio of the hypergravity- to apomorphine-induced kaolin intakes. These results indicate that HL aggravates motion sickness induced by hypergravity in rats, suggesting that the hippocampus counteracts motion sickness.


American Journal of Otolaryngology | 1990

Positional nystagmus and body sway after alcohol ingestion

Takeshi Kubo; Yoshiharu Sakata; A. Koshimune; Shun-ichi Sakai; K. Ameno; I. Ijiri

Positional nystagmus and body sway were measured for 8 hours following alcohol ingestion in 27 human volunteers. The intensity of positional alcohol nystagmus phase I (PAN-I) correlated well with blood alcohol concentration (BAC) along the time axis; the correlation coefficient between PAN-I and BAC 1 hour after alcohol ingestion was 0.62 (P less than .01). The minimum threshold BAC resulting in PAN-I was 0.23 mg/mL. Body sway was measured by stabilometry. The circumscribed area of posturography before and after alcohol ingestion was compared. Temporal changes in body sway and BAC were also closely correlated. The BAC threshold for increased body sway was estimated to be somewhere between 0.5 and 0.8 mg/mL, considerably higher than the threshold for PAN-I. Measurements of blood acetaldehyde, the dehydrated product of ethanol metabolism, showed no correlation with either the intensity of PAN or changes in body sway. The intensity of PAN and body sway measured at the time of peak BAC 1 hour after alcohol ingestion, however, showed significant positive correlation (r = .50, n = 25; P less than .01).


Acta Oto-laryngologica | 1988

Clinical Observations in the Acute Phase of Cerebellar Hemorrhage and Infarction

Takeshi Kubo; Yoshiharu Sakata; Shun-ichi Sakai; Izumi Koizuka; Toru Matsunaga; Tokuji Nogawa

Three cases of cerebellar hemorrhage and 5 of cerebellar infarction, diagnosed by brain CT, were examined from the early phase of the onset. All of our cases were mild to moderate in severity and were cured satisfactorily within 3 to 8 weeks of medical treatment. Dizziness and nausea were the commonest symptoms and cerebellar and other CNS signs could be detected only for a short period in some of the cases. Although neuro-otological examinations, especially gaze nystagmus, eye tracking and positional nystagmus tests, were useful for diagnosing the central vestibular lesion, no definite indication could be drawn in order to differentiate between cerebellar hemorrhage and infarction. Therefore, it is considered difficult in such mild cerebellar strokes to establish correct diagnosis by physical examinations alone. It was concluded that if central vestibular disorder is suspected, prompt brain CT examination is necessary in order to diagnose mild cases of cerebellar vascular diseases.


Acta Oto-laryngologica | 2000

Effects of vestibular cerebellum lesion on motion sickness in rats.

Atsuhiko Uno; Noriaki Takeda; Tadashi Kitahara; Yoshiharu Sakata; Atsushi Yamatodani; Takeshi Kubo

The importance of the vestibular apparatus in the development of motion sickness is widely accepted, although the role of the vestibular cerebellum remains controversial. We examined the effects of vestibular cerebellum lesion on the development of motion sickness in rats. Rats do not vomit, but the behaviour known as ?pica?, the eating of non-nutritive substances, such as kaolin, can be used as an index of motion sickness. A 2 h load of hypergravity induced pica in rats, indicating that they suffered from motion sickness. Pica was induced by hypergravity load even after surgical lesion to the bilateral cerebellar flocculus or to the cerebellar vermis. We concluded that the vestibular cerebellum was not essential in the development of motion sickness in rats.


Acta Oto-laryngologica | 2005

Brain herniation into the middle ear following temporal bone fracture

Suetaka Nishiike; Yasuyoshi Miyao; Seiichi Gouda; Nobumitsu Shimada; Miki Nagai; Aya Nakagawa; Masaki Konishi; Yoshiharu Sakata

Otorrhea of leaked cerebrospinal fluid and meningitis in a 33-year-old male originated from an encephalic herniation into the middle ear following traumatic temporal bone fracture. CT demonstrated a mixed-type fracture consisting of a longitudinal fracture and a posterior oblique fracture of the left temporal bone. The left tegmen tympani was broken into a bellows-like shape and a bone splinter from it had stuck in the epitympanum at the level of the incus body. Surgery via a middle cranial fossa approach confirmed penetration of the brain tissue between the incus and lateral semicircular canal. The diagnosis and management of this condition are discussed in the context of a literature review.


Acta Oto-laryngologica | 1991

Analysis of Saccadic Eye Movements Using an Infrared Video System in Human Subjects

Takeshi Kubo; Takanori Saika; Yoshiharu Sakata; Yasuhiro Morita; Toru Matsunaga; Tatsuya Kasahara

Horizontal and vertical saccades were recorded and quantitatively analyzed with an infrared video recording system in 6 normal human subjects. Peak and mean saccade velocities increased exponentially as the amplitude increased. Peak velocity of horizontal saccade was significantly larger than that of vertical saccade (p less than 0.05, ANOVA test). On the other hand, duration and latency showed a linear relationship with saccade amplitude. Latency was constant (i.e. 0.21 s) irrespective of saccade amplitude in the regular eye tracking mode; however, latency slightly increased as the amplitude became larger in the randomized eye tracking mode. As a result, a slight positive correlation could be found between saccade amplitude and latency: r = 0.50 and 0.35 in horizontal and vertical saccades, respectively.


Acta Oto-laryngologica | 2004

Management and Follow-up of Localized Wegener's Granulomatosis: A Review of Five Cases

Suetaka Nishiike; Takashi Kato; Miki Nagai; Masaki Konishi; Yoshiharu Sakata

Objective —To evaluate the complications, efficacy of surgical treatment and outcome in patients with the localized form of Wegeners granulomatosis (WG). Materials and Methods —We reviewed a series of 5 patients (3 males, 2 females; age range 22–67 years; mean age 44.6 years) with WG in the upper and lower respiratory tracts. Results —Aural, nasal and ocular complications were common in our patients. All patients responded to standard immunosuppressive treatment, and all surgical treatments had a favorable outcome in the remission stage. Although there was no life-threatening disease activity during the course of treatment, minor relapses occurred in three patients. Conclusions —Patients with localized WG may have a better outcome than those with systemic WG, but complications due to the disease or medication must be actively managed. Reconstructive surgery for patients with WG is safe and effective during the remission stage.

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Izumi Koizuka

St. Marianna University School of Medicine

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